Passive matrix organic light emitting display panels having touch sensors using anode and cathode electrodes

Abstract

A PMOLED touch-sensing display panel using anodes as in-cell touch sensors is provided. The anodes and the cathodes are respectively and correspondingly configured into two or more electrically isolated areas of cathodes and anodes such that the heavy parasitic capacitance due to close proximity of the anode layer and the cathode layer is eliminated, hence providing a full dynamic range in sensing the changes in capacitance due to finger touches.

What is claimed is: 
     
       1. A touch-sensing display panel, comprising:
 a first electrode layer consists of a plurality of first electrodes running in parallel to each other; 
 an second electrode layer consists of a plurality of second electrodes running in a direction perpendicular to the first electrodes; 
 a layer of electroluminescent materials being held in between the first electrode layer and the second electrode layer; and 
 at least one touch-sensing controller; 
 wherein each of the first electrodes is split into two or more first sub-electrodes forming two or more areas of first sub-electrodes; and 
 wherein each of the second electrodes are grouped to form two or more areas of second electrodes; and 
 wherein each overlapping area of each of the areas of first sub-electrodes and each of the areas of second electrodes serves as a touch-sensing key with signals from the second electrodes in each of the area of second electrodes are summed by the touch-sensing controller to produce an output-channel signal for touch sensing during a time-multiplexed touch-sensing mode. 
 
     
     
       2. The touch-sensing display panel of  claim 1 ,
 wherein each of the second electrodes is split into two or more second sub-electrodes forming two or more areas of second sub-electrodes; and 
 wherein each overlapping area of each of the areas of first sub-electrodes and each of the areas of second sub-electrodes serves as a touch-sensing key with signals from the second sub-electrodes in each of the area of second sub-electrodes are summed by the touch-sensing controller to produce an output-channel signal for touch sensing during the time-multiplexed touch-sensing mode. 
 
     
     
       3. The touch-sensing display panel of  claim 2 ,
 wherein the first electrodes are running in the horizontal direction of the touch-sensing display panel; and 
 wherein more than one first electrode are driven at any one instance during a time-multiplexed display-driving mode. 
 
     
     
       4. The touch-sensing display panel of  claim 2 ,
 wherein the first electrodes are running in the vertical direction of the touch-sensing display panel; and 
 wherein more than one first electrode are driven at any one instance during a time-multiplexed display-driving mode. 
 
     
     
       5. The touch-sensing display panel of  claim 2 ,
 wherein the first electrodes are cathodes, the first sub-electrodes are sub-cathodes, the second electrodes are anodes, and the second sub-electrodes are sub-anodes; 
 wherein the overlapping areas of the areas of first sub-electrodes and the areas of second sub-electrodes are configured in a two-dimensional touch-sensing key array. 
 
     
     
       6. The touch-sensing display panel of  claim 2 , further comprising:
 a first display driver located at a first side of the touch-sensing display panel; and 
 a second display driver located at a second side of the touch-sensing display panel, wherein the second side is opposite of the first side; 
 wherein the first sub-electrodes and the second sub-electrodes that are closer to the first side of the touch-sensing display panel than to the second side of the touch-sensing display panel are connected to the first display driver and driven by the first display driver during a time-multiplexed display-driving mode; and 
 wherein the first sub-electrodes and the second sub-electrodes that are closer to the second side of the touch-sensing display panel than to the first side of the touch-sensing display panel are connected to the second display driver and driven by the second display driver during a time-multiplexed display-driving mode. 
 
     
     
       7. The touch-sensing display panel of  claim 2 ,
 wherein the first sub-electrodes are connected to high impedance during the time-multiplexed touch-sensing mode. 
 
     
     
       8. The touch-sensing display panel of  claim 2 ,
 wherein the touch-sensing controller comprises a plurality of micro-switches; and 
 the first sub-electrodes and second sub-electrodes are shorted by the micro-switches during the time-multiplexed touch-sensing mode. 
 
     
     
       9. The touch-sensing display panel of  claim 1 , wherein during the time-multiplexed touch-sensing mode, each of the first sub-electrodes are connected to a high impedance and each group of first sub-electrodes split from the same first electrode is configured to eliminate a parasitic capacitance between each crossing of the first sub-electrodes and second electrodes. 
     
     
       10. The touch-sensing display panel of  claim 1 ,
 wherein the first electrodes are cathodes, the first sub-electrodes are sub-cathodes, and the second electrodes are anodes; 
 wherein the areas of first sub-electrodes are configured in a one-dimensional touch-sensing key array.